| 摘要 |
Provided is a refractory material having both excellent erosion/corrosion resistance and thermal shock resistance, which has hardly been obtainable by conventional techniques, and a casting nozzle using the refractory material. The refractory material of the present invention contains: MgO in an amount of 40 mass% or more; a free carbon component in an amount of 4 to 30 mass%; and one or more selected from the group consisting of B 2 O 3 , P 2 O 5 , SiO 2 and TiO 2 , in a total amount of 0.3 to 3 mass%, with the remainder being at least one other type of additional refractory component, wherein a void layer exists in an interface between a carbon-containing matrix microstructure residing at least on opposite sides of a maximum-size one of a plurality of MgO-containing particles in the refractory material, and the maximum-size MgO-containing particle, wherein a sum of respective thicknesses of the void layer at two positions on the opposite sides is 0.2 to 3.0% in terms of a ratio with respect to a particle size of the maximum-size MgO-containing particle, and wherein an inorganic compound comprised of MgO and the one or more selected from the group consisting of B 2 O 3 , P 2 O 5 , SiO 2 and TiO 2 exists in an entirety or a part of a surface of each of the plurality of MgO-containing particles. |
